Cristhian Bahena Rivera, the man accused of killing University of Iowa student Mollie Tibbets, was arraigned Wednesday on first-degree murder charges at the Poweshiek County District Court in Montezuma, Iowa, with his trial set for next April.

Rivera entered a not guilty plea in court, through an interpreter, with a trial date of April 16 in Poweshiek County District Court, which was live streamed by Des Moines Register.com. He remained in custody after the arraignment under a $5 million cash-only bond, set when he was initially arrested last month.

Authorities arrested Rivera, 24, a Mexican national, last month in connection with Tibbets’ murder, which attracted national attention during her disappearance, KCCI-TV reported. She went missing while on a run in Brooklyn, Iowa, in July, the television station stated.

Her body was eventually found in a cornfield, KCCI-TV stated. An award of nearly $400,000 was offered on Tibbetts’ whereabouts when the 20-year-old psychology student went missing on July 18, according to CNN.

Authorities charged that Rivera led them to Tibbetts’ body after telling them he saw and pursued the student on her jog, the network reported.

Rivera claimed, according to police, that he blacked out at some point, but was able to take them to Tibbetts’ body that was covered in corn leaves, per CNN. Rick Rahn, an Iowa Division of Criminal Investigation special agent, said a motive in the crime was not clear.

“I can’t really speak to you about the motive,” Rahn told CNN. “I can just tell you it seems that he followed her and seemed to be drawn to her on that particular day and for whatever reason he chose to abduct her.”

Tibbetts’ death has taken on a political tone because Rivera has been identified as an undocumented immigrant who has lived in the Iowa area from four to seven years, the network said.

The Trump administration has made illegal immigration one of its top issues since taking office last year and have used such crimes in the past as evidence of stronger measures against those who cross the border illegally.

“You heard about today with the illegal alien coming in very sadly from Mexico,” Trump said at a rally last month in an effort to turn Tibbetts’ death into a campaign issue, CNN reported. “And you saw what happened to that incredible beautiful young woman. Should have never happened. Illegally in our country. We’ve had a huge impact but the laws are so bad, the immigration laws are such a disgrace. We’re getting it changed but we have to get more Republicans.”